uboot/drivers/i2c/mxc_i2c.c
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   1/*
   2 * i2c driver for Freescale i.MX series
   3 *
   4 * (c) 2007 Pengutronix, Sascha Hauer <s.hauer@pengutronix.de>
   5 * (c) 2011 Marek Vasut <marek.vasut@gmail.com>
   6 *
   7 * Based on i2c-imx.c from linux kernel:
   8 *  Copyright (C) 2005 Torsten Koschorrek <koschorrek at synertronixx.de>
   9 *  Copyright (C) 2005 Matthias Blaschke <blaschke at synertronixx.de>
  10 *  Copyright (C) 2007 RightHand Technologies, Inc.
  11 *  Copyright (C) 2008 Darius Augulis <darius.augulis at teltonika.lt>
  12 *
  13 *
  14 * SPDX-License-Identifier:     GPL-2.0+
  15 */
  16
  17#include <common.h>
  18#include <asm/arch/clock.h>
  19#include <asm/arch/imx-regs.h>
  20#include <linux/errno.h>
  21#include <asm/imx-common/mxc_i2c.h>
  22#include <asm/io.h>
  23#include <i2c.h>
  24#include <watchdog.h>
  25#include <dm.h>
  26#include <dm/pinctrl.h>
  27#include <fdtdec.h>
  28
  29DECLARE_GLOBAL_DATA_PTR;
  30
  31#define I2C_QUIRK_FLAG          (1 << 0)
  32
  33#define IMX_I2C_REGSHIFT        2
  34#define VF610_I2C_REGSHIFT      0
  35
  36#define I2C_EARLY_INIT_INDEX            0
  37#ifdef CONFIG_SYS_I2C_IFDR_DIV
  38#define I2C_IFDR_DIV_CONSERVATIVE       CONFIG_SYS_I2C_IFDR_DIV
  39#else
  40#define I2C_IFDR_DIV_CONSERVATIVE       0x7e
  41#endif
  42
  43/* Register index */
  44#define IADR    0
  45#define IFDR    1
  46#define I2CR    2
  47#define I2SR    3
  48#define I2DR    4
  49
  50#define I2CR_IIEN       (1 << 6)
  51#define I2CR_MSTA       (1 << 5)
  52#define I2CR_MTX        (1 << 4)
  53#define I2CR_TX_NO_AK   (1 << 3)
  54#define I2CR_RSTA       (1 << 2)
  55
  56#define I2SR_ICF        (1 << 7)
  57#define I2SR_IBB        (1 << 5)
  58#define I2SR_IAL        (1 << 4)
  59#define I2SR_IIF        (1 << 1)
  60#define I2SR_RX_NO_AK   (1 << 0)
  61
  62#ifdef I2C_QUIRK_REG
  63#define I2CR_IEN        (0 << 7)
  64#define I2CR_IDIS       (1 << 7)
  65#define I2SR_IIF_CLEAR  (1 << 1)
  66#else
  67#define I2CR_IEN        (1 << 7)
  68#define I2CR_IDIS       (0 << 7)
  69#define I2SR_IIF_CLEAR  (0 << 1)
  70#endif
  71
  72#if defined(CONFIG_HARD_I2C) && !defined(CONFIG_SYS_I2C_BASE)
  73#error "define CONFIG_SYS_I2C_BASE to use the mxc_i2c driver"
  74#endif
  75
  76#ifdef I2C_QUIRK_REG
  77static u16 i2c_clk_div[60][2] = {
  78        { 20,   0x00 }, { 22,   0x01 }, { 24,   0x02 }, { 26,   0x03 },
  79        { 28,   0x04 }, { 30,   0x05 }, { 32,   0x09 }, { 34,   0x06 },
  80        { 36,   0x0A }, { 40,   0x07 }, { 44,   0x0C }, { 48,   0x0D },
  81        { 52,   0x43 }, { 56,   0x0E }, { 60,   0x45 }, { 64,   0x12 },
  82        { 68,   0x0F }, { 72,   0x13 }, { 80,   0x14 }, { 88,   0x15 },
  83        { 96,   0x19 }, { 104,  0x16 }, { 112,  0x1A }, { 128,  0x17 },
  84        { 136,  0x4F }, { 144,  0x1C }, { 160,  0x1D }, { 176,  0x55 },
  85        { 192,  0x1E }, { 208,  0x56 }, { 224,  0x22 }, { 228,  0x24 },
  86        { 240,  0x1F }, { 256,  0x23 }, { 288,  0x5C }, { 320,  0x25 },
  87        { 384,  0x26 }, { 448,  0x2A }, { 480,  0x27 }, { 512,  0x2B },
  88        { 576,  0x2C }, { 640,  0x2D }, { 768,  0x31 }, { 896,  0x32 },
  89        { 960,  0x2F }, { 1024, 0x33 }, { 1152, 0x34 }, { 1280, 0x35 },
  90        { 1536, 0x36 }, { 1792, 0x3A }, { 1920, 0x37 }, { 2048, 0x3B },
  91        { 2304, 0x3C }, { 2560, 0x3D }, { 3072, 0x3E }, { 3584, 0x7A },
  92        { 3840, 0x3F }, { 4096, 0x7B }, { 5120, 0x7D }, { 6144, 0x7E },
  93};
  94#else
  95static u16 i2c_clk_div[50][2] = {
  96        { 22,   0x20 }, { 24,   0x21 }, { 26,   0x22 }, { 28,   0x23 },
  97        { 30,   0x00 }, { 32,   0x24 }, { 36,   0x25 }, { 40,   0x26 },
  98        { 42,   0x03 }, { 44,   0x27 }, { 48,   0x28 }, { 52,   0x05 },
  99        { 56,   0x29 }, { 60,   0x06 }, { 64,   0x2A }, { 72,   0x2B },
 100        { 80,   0x2C }, { 88,   0x09 }, { 96,   0x2D }, { 104,  0x0A },
 101        { 112,  0x2E }, { 128,  0x2F }, { 144,  0x0C }, { 160,  0x30 },
 102        { 192,  0x31 }, { 224,  0x32 }, { 240,  0x0F }, { 256,  0x33 },
 103        { 288,  0x10 }, { 320,  0x34 }, { 384,  0x35 }, { 448,  0x36 },
 104        { 480,  0x13 }, { 512,  0x37 }, { 576,  0x14 }, { 640,  0x38 },
 105        { 768,  0x39 }, { 896,  0x3A }, { 960,  0x17 }, { 1024, 0x3B },
 106        { 1152, 0x18 }, { 1280, 0x3C }, { 1536, 0x3D }, { 1792, 0x3E },
 107        { 1920, 0x1B }, { 2048, 0x3F }, { 2304, 0x1C }, { 2560, 0x1D },
 108        { 3072, 0x1E }, { 3840, 0x1F }
 109};
 110#endif
 111
 112#ifndef CONFIG_SYS_MXC_I2C1_SPEED
 113#define CONFIG_SYS_MXC_I2C1_SPEED 100000
 114#endif
 115#ifndef CONFIG_SYS_MXC_I2C2_SPEED
 116#define CONFIG_SYS_MXC_I2C2_SPEED 100000
 117#endif
 118#ifndef CONFIG_SYS_MXC_I2C3_SPEED
 119#define CONFIG_SYS_MXC_I2C3_SPEED 100000
 120#endif
 121#ifndef CONFIG_SYS_MXC_I2C4_SPEED
 122#define CONFIG_SYS_MXC_I2C4_SPEED 100000
 123#endif
 124
 125#ifndef CONFIG_SYS_MXC_I2C1_SLAVE
 126#define CONFIG_SYS_MXC_I2C1_SLAVE 0
 127#endif
 128#ifndef CONFIG_SYS_MXC_I2C2_SLAVE
 129#define CONFIG_SYS_MXC_I2C2_SLAVE 0
 130#endif
 131#ifndef CONFIG_SYS_MXC_I2C3_SLAVE
 132#define CONFIG_SYS_MXC_I2C3_SLAVE 0
 133#endif
 134#ifndef CONFIG_SYS_MXC_I2C4_SLAVE
 135#define CONFIG_SYS_MXC_I2C4_SLAVE 0
 136#endif
 137
 138/*
 139 * Calculate and set proper clock divider
 140 */
 141static uint8_t i2c_imx_get_clk(struct mxc_i2c_bus *i2c_bus, unsigned int rate)
 142{
 143        unsigned int i2c_clk_rate;
 144        unsigned int div;
 145        u8 clk_div;
 146
 147#if defined(CONFIG_MX31)
 148        struct clock_control_regs *sc_regs =
 149                (struct clock_control_regs *)CCM_BASE;
 150
 151        /* start the required I2C clock */
 152        writel(readl(&sc_regs->cgr0) | (3 << CONFIG_SYS_I2C_CLK_OFFSET),
 153                &sc_regs->cgr0);
 154#endif
 155
 156        /* Divider value calculation */
 157        i2c_clk_rate = mxc_get_clock(MXC_I2C_CLK);
 158        div = (i2c_clk_rate + rate - 1) / rate;
 159        if (div < i2c_clk_div[0][0])
 160                clk_div = 0;
 161        else if (div > i2c_clk_div[ARRAY_SIZE(i2c_clk_div) - 1][0])
 162                clk_div = ARRAY_SIZE(i2c_clk_div) - 1;
 163        else
 164                for (clk_div = 0; i2c_clk_div[clk_div][0] < div; clk_div++)
 165                        ;
 166
 167        /* Store divider value */
 168        return clk_div;
 169}
 170
 171/*
 172 * Set I2C Bus speed
 173 */
 174static int bus_i2c_set_bus_speed(struct mxc_i2c_bus *i2c_bus, int speed)
 175{
 176        ulong base = i2c_bus->base;
 177        bool quirk = i2c_bus->driver_data & I2C_QUIRK_FLAG ? true : false;
 178        u8 clk_idx = i2c_imx_get_clk(i2c_bus, speed);
 179        u8 idx = i2c_clk_div[clk_idx][1];
 180        int reg_shift = quirk ? VF610_I2C_REGSHIFT : IMX_I2C_REGSHIFT;
 181
 182        if (!base)
 183                return -ENODEV;
 184
 185        /* Store divider value */
 186        writeb(idx, base + (IFDR << reg_shift));
 187
 188        /* Reset module */
 189        writeb(I2CR_IDIS, base + (I2CR << reg_shift));
 190        writeb(0, base + (I2SR << reg_shift));
 191        return 0;
 192}
 193
 194#define ST_BUS_IDLE (0 | (I2SR_IBB << 8))
 195#define ST_BUS_BUSY (I2SR_IBB | (I2SR_IBB << 8))
 196#define ST_IIF (I2SR_IIF | (I2SR_IIF << 8))
 197
 198static int wait_for_sr_state(struct mxc_i2c_bus *i2c_bus, unsigned state)
 199{
 200        unsigned sr;
 201        ulong elapsed;
 202        bool quirk = i2c_bus->driver_data & I2C_QUIRK_FLAG ? true : false;
 203        int reg_shift = quirk ? VF610_I2C_REGSHIFT : IMX_I2C_REGSHIFT;
 204        ulong base = i2c_bus->base;
 205        ulong start_time = get_timer(0);
 206        for (;;) {
 207                sr = readb(base + (I2SR << reg_shift));
 208                if (sr & I2SR_IAL) {
 209                        if (quirk)
 210                                writeb(sr | I2SR_IAL, base +
 211                                       (I2SR << reg_shift));
 212                        else
 213                                writeb(sr & ~I2SR_IAL, base +
 214                                       (I2SR << reg_shift));
 215                        printf("%s: Arbitration lost sr=%x cr=%x state=%x\n",
 216                                __func__, sr, readb(base + (I2CR << reg_shift)),
 217                                state);
 218                        return -ERESTART;
 219                }
 220                if ((sr & (state >> 8)) == (unsigned char)state)
 221                        return sr;
 222                WATCHDOG_RESET();
 223                elapsed = get_timer(start_time);
 224                if (elapsed > (CONFIG_SYS_HZ / 10))     /* .1 seconds */
 225                        break;
 226        }
 227        printf("%s: failed sr=%x cr=%x state=%x\n", __func__,
 228               sr, readb(base + (I2CR << reg_shift)), state);
 229        return -ETIMEDOUT;
 230}
 231
 232static int tx_byte(struct mxc_i2c_bus *i2c_bus, u8 byte)
 233{
 234        int ret;
 235        int reg_shift = i2c_bus->driver_data & I2C_QUIRK_FLAG ?
 236                        VF610_I2C_REGSHIFT : IMX_I2C_REGSHIFT;
 237        ulong base = i2c_bus->base;
 238
 239        writeb(I2SR_IIF_CLEAR, base + (I2SR << reg_shift));
 240        writeb(byte, base + (I2DR << reg_shift));
 241
 242        ret = wait_for_sr_state(i2c_bus, ST_IIF);
 243        if (ret < 0)
 244                return ret;
 245        if (ret & I2SR_RX_NO_AK)
 246                return -ENODEV;
 247        return 0;
 248}
 249
 250/*
 251 * Stub implementations for outer i2c slave operations.
 252 */
 253void __i2c_force_reset_slave(void)
 254{
 255}
 256void i2c_force_reset_slave(void)
 257        __attribute__((weak, alias("__i2c_force_reset_slave")));
 258
 259/*
 260 * Stop I2C transaction
 261 */
 262static void i2c_imx_stop(struct mxc_i2c_bus *i2c_bus)
 263{
 264        int ret;
 265        int reg_shift = i2c_bus->driver_data & I2C_QUIRK_FLAG ?
 266                        VF610_I2C_REGSHIFT : IMX_I2C_REGSHIFT;
 267        ulong base = i2c_bus->base;
 268        unsigned int temp = readb(base + (I2CR << reg_shift));
 269
 270        temp &= ~(I2CR_MSTA | I2CR_MTX);
 271        writeb(temp, base + (I2CR << reg_shift));
 272        ret = wait_for_sr_state(i2c_bus, ST_BUS_IDLE);
 273        if (ret < 0)
 274                printf("%s:trigger stop failed\n", __func__);
 275}
 276
 277/*
 278 * Send start signal, chip address and
 279 * write register address
 280 */
 281static int i2c_init_transfer_(struct mxc_i2c_bus *i2c_bus, u8 chip,
 282                              u32 addr, int alen)
 283{
 284        unsigned int temp;
 285        int ret;
 286        bool quirk = i2c_bus->driver_data & I2C_QUIRK_FLAG ? true : false;
 287        ulong base = i2c_bus->base;
 288        int reg_shift = quirk ? VF610_I2C_REGSHIFT : IMX_I2C_REGSHIFT;
 289
 290        /* Reset i2c slave */
 291        i2c_force_reset_slave();
 292
 293        /* Enable I2C controller */
 294        if (quirk)
 295                ret = readb(base + (I2CR << reg_shift)) & I2CR_IDIS;
 296        else
 297                ret = !(readb(base + (I2CR << reg_shift)) & I2CR_IEN);
 298
 299        if (ret) {
 300                writeb(I2CR_IEN, base + (I2CR << reg_shift));
 301                /* Wait for controller to be stable */
 302                udelay(50);
 303        }
 304
 305        if (readb(base + (IADR << reg_shift)) == (chip << 1))
 306                writeb((chip << 1) ^ 2, base + (IADR << reg_shift));
 307        writeb(I2SR_IIF_CLEAR, base + (I2SR << reg_shift));
 308        ret = wait_for_sr_state(i2c_bus, ST_BUS_IDLE);
 309        if (ret < 0)
 310                return ret;
 311
 312        /* Start I2C transaction */
 313        temp = readb(base + (I2CR << reg_shift));
 314        temp |= I2CR_MSTA;
 315        writeb(temp, base + (I2CR << reg_shift));
 316
 317        ret = wait_for_sr_state(i2c_bus, ST_BUS_BUSY);
 318        if (ret < 0)
 319                return ret;
 320
 321        temp |= I2CR_MTX | I2CR_TX_NO_AK;
 322        writeb(temp, base + (I2CR << reg_shift));
 323
 324        /* write slave address */
 325        ret = tx_byte(i2c_bus, chip << 1);
 326        if (ret < 0)
 327                return ret;
 328
 329        while (alen--) {
 330                ret = tx_byte(i2c_bus, (addr >> (alen * 8)) & 0xff);
 331                if (ret < 0)
 332                        return ret;
 333        }
 334        return 0;
 335}
 336
 337#ifndef CONFIG_DM_I2C
 338int i2c_idle_bus(struct mxc_i2c_bus *i2c_bus)
 339{
 340        if (i2c_bus && i2c_bus->idle_bus_fn)
 341                return i2c_bus->idle_bus_fn(i2c_bus->idle_bus_data);
 342        return 0;
 343}
 344#else
 345/*
 346 * See Linux Documentation/devicetree/bindings/i2c/i2c-imx.txt
 347 * "
 348 *  scl-gpios: specify the gpio related to SCL pin
 349 *  sda-gpios: specify the gpio related to SDA pin
 350 *  add pinctrl to configure i2c pins to gpio function for i2c
 351 *  bus recovery, call it "gpio" state
 352 * "
 353 *
 354 * The i2c_idle_bus is an implementation following Linux Kernel.
 355 */
 356int i2c_idle_bus(struct mxc_i2c_bus *i2c_bus)
 357{
 358        struct udevice *bus = i2c_bus->bus;
 359        struct gpio_desc *scl_gpio = &i2c_bus->scl_gpio;
 360        struct gpio_desc *sda_gpio = &i2c_bus->sda_gpio;
 361        int sda, scl;
 362        int i, ret = 0;
 363        ulong elapsed, start_time;
 364
 365        if (pinctrl_select_state(bus, "gpio")) {
 366                dev_dbg(bus, "Can not to switch to use gpio pinmux\n");
 367                /*
 368                 * GPIO pinctrl for i2c force idle is not a must,
 369                 * but it is strongly recommended to be used.
 370                 * Because it can help you to recover from bad
 371                 * i2c bus state. Do not return failure, because
 372                 * it is not a must.
 373                 */
 374                return 0;
 375        }
 376
 377        dm_gpio_set_dir_flags(scl_gpio, GPIOD_IS_IN);
 378        dm_gpio_set_dir_flags(sda_gpio, GPIOD_IS_IN);
 379        scl = dm_gpio_get_value(scl_gpio);
 380        sda = dm_gpio_get_value(sda_gpio);
 381
 382        if ((sda & scl) == 1)
 383                goto exit;              /* Bus is idle already */
 384
 385        /* Send high and low on the SCL line */
 386        for (i = 0; i < 9; i++) {
 387                dm_gpio_set_dir_flags(scl_gpio, GPIOD_IS_OUT);
 388                dm_gpio_set_value(scl_gpio, 0);
 389                udelay(50);
 390                dm_gpio_set_dir_flags(scl_gpio, GPIOD_IS_IN);
 391                udelay(50);
 392        }
 393        start_time = get_timer(0);
 394        for (;;) {
 395                dm_gpio_set_dir_flags(scl_gpio, GPIOD_IS_IN);
 396                dm_gpio_set_dir_flags(sda_gpio, GPIOD_IS_IN);
 397                scl = dm_gpio_get_value(scl_gpio);
 398                sda = dm_gpio_get_value(sda_gpio);
 399                if ((sda & scl) == 1)
 400                        break;
 401                WATCHDOG_RESET();
 402                elapsed = get_timer(start_time);
 403                if (elapsed > (CONFIG_SYS_HZ / 5)) {    /* .2 seconds */
 404                        ret = -EBUSY;
 405                        printf("%s: failed to clear bus, sda=%d scl=%d\n", __func__, sda, scl);
 406                        break;
 407                }
 408        }
 409
 410exit:
 411        pinctrl_select_state(bus, "default");
 412        return ret;
 413}
 414#endif
 415
 416static int i2c_init_transfer(struct mxc_i2c_bus *i2c_bus, u8 chip,
 417                             u32 addr, int alen)
 418{
 419        int retry;
 420        int ret;
 421        int reg_shift = i2c_bus->driver_data & I2C_QUIRK_FLAG ?
 422                        VF610_I2C_REGSHIFT : IMX_I2C_REGSHIFT;
 423
 424        if (!i2c_bus->base)
 425                return -ENODEV;
 426
 427        for (retry = 0; retry < 3; retry++) {
 428                ret = i2c_init_transfer_(i2c_bus, chip, addr, alen);
 429                if (ret >= 0)
 430                        return 0;
 431                i2c_imx_stop(i2c_bus);
 432                if (ret == -ENODEV)
 433                        return ret;
 434
 435                printf("%s: failed for chip 0x%x retry=%d\n", __func__, chip,
 436                                retry);
 437                if (ret != -ERESTART)
 438                        /* Disable controller */
 439                        writeb(I2CR_IDIS, i2c_bus->base + (I2CR << reg_shift));
 440                udelay(100);
 441                if (i2c_idle_bus(i2c_bus) < 0)
 442                        break;
 443        }
 444        printf("%s: give up i2c_regs=0x%lx\n", __func__, i2c_bus->base);
 445        return ret;
 446}
 447
 448
 449static int i2c_write_data(struct mxc_i2c_bus *i2c_bus, u8 chip, const u8 *buf,
 450                          int len)
 451{
 452        int i, ret = 0;
 453
 454        debug("i2c_write_data: chip=0x%x, len=0x%x\n", chip, len);
 455        debug("write_data: ");
 456        /* use rc for counter */
 457        for (i = 0; i < len; ++i)
 458                debug(" 0x%02x", buf[i]);
 459        debug("\n");
 460
 461        for (i = 0; i < len; i++) {
 462                ret = tx_byte(i2c_bus, buf[i]);
 463                if (ret < 0) {
 464                        debug("i2c_write_data(): rc=%d\n", ret);
 465                        break;
 466                }
 467        }
 468
 469        return ret;
 470}
 471
 472static int i2c_read_data(struct mxc_i2c_bus *i2c_bus, uchar chip, uchar *buf,
 473                         int len)
 474{
 475        int ret;
 476        unsigned int temp;
 477        int i;
 478        int reg_shift = i2c_bus->driver_data & I2C_QUIRK_FLAG ?
 479                        VF610_I2C_REGSHIFT : IMX_I2C_REGSHIFT;
 480        ulong base = i2c_bus->base;
 481
 482        debug("i2c_read_data: chip=0x%x, len=0x%x\n", chip, len);
 483
 484        /* setup bus to read data */
 485        temp = readb(base + (I2CR << reg_shift));
 486        temp &= ~(I2CR_MTX | I2CR_TX_NO_AK);
 487        if (len == 1)
 488                temp |= I2CR_TX_NO_AK;
 489        writeb(temp, base + (I2CR << reg_shift));
 490        writeb(I2SR_IIF_CLEAR, base + (I2SR << reg_shift));
 491        /* dummy read to clear ICF */
 492        readb(base + (I2DR << reg_shift));
 493
 494        /* read data */
 495        for (i = 0; i < len; i++) {
 496                ret = wait_for_sr_state(i2c_bus, ST_IIF);
 497                if (ret < 0) {
 498                        debug("i2c_read_data(): ret=%d\n", ret);
 499                        i2c_imx_stop(i2c_bus);
 500                        return ret;
 501                }
 502
 503                /*
 504                 * It must generate STOP before read I2DR to prevent
 505                 * controller from generating another clock cycle
 506                 */
 507                if (i == (len - 1)) {
 508                        i2c_imx_stop(i2c_bus);
 509                } else if (i == (len - 2)) {
 510                        temp = readb(base + (I2CR << reg_shift));
 511                        temp |= I2CR_TX_NO_AK;
 512                        writeb(temp, base + (I2CR << reg_shift));
 513                }
 514                writeb(I2SR_IIF_CLEAR, base + (I2SR << reg_shift));
 515                buf[i] = readb(base + (I2DR << reg_shift));
 516        }
 517
 518        /* reuse ret for counter*/
 519        for (ret = 0; ret < len; ++ret)
 520                debug(" 0x%02x", buf[ret]);
 521        debug("\n");
 522
 523        i2c_imx_stop(i2c_bus);
 524        return 0;
 525}
 526
 527#ifndef CONFIG_DM_I2C
 528/*
 529 * Read data from I2C device
 530 */
 531static int bus_i2c_read(struct mxc_i2c_bus *i2c_bus, u8 chip, u32 addr,
 532                        int alen, u8 *buf, int len)
 533{
 534        int ret = 0;
 535        u32 temp;
 536        int reg_shift = i2c_bus->driver_data & I2C_QUIRK_FLAG ?
 537                VF610_I2C_REGSHIFT : IMX_I2C_REGSHIFT;
 538        ulong base = i2c_bus->base;
 539
 540        ret = i2c_init_transfer(i2c_bus, chip, addr, alen);
 541        if (ret < 0)
 542                return ret;
 543
 544        temp = readb(base + (I2CR << reg_shift));
 545        temp |= I2CR_RSTA;
 546        writeb(temp, base + (I2CR << reg_shift));
 547
 548        ret = tx_byte(i2c_bus, (chip << 1) | 1);
 549        if (ret < 0) {
 550                i2c_imx_stop(i2c_bus);
 551                return ret;
 552        }
 553
 554        ret = i2c_read_data(i2c_bus, chip, buf, len);
 555
 556        i2c_imx_stop(i2c_bus);
 557        return ret;
 558}
 559
 560/*
 561 * Write data to I2C device
 562 */
 563static int bus_i2c_write(struct mxc_i2c_bus *i2c_bus, u8 chip, u32 addr,
 564                         int alen, const u8 *buf, int len)
 565{
 566        int ret = 0;
 567
 568        ret = i2c_init_transfer(i2c_bus, chip, addr, alen);
 569        if (ret < 0)
 570                return ret;
 571
 572        ret = i2c_write_data(i2c_bus, chip, buf, len);
 573
 574        i2c_imx_stop(i2c_bus);
 575
 576        return ret;
 577}
 578
 579#if !defined(I2C2_BASE_ADDR)
 580#define I2C2_BASE_ADDR  0
 581#endif
 582
 583#if !defined(I2C3_BASE_ADDR)
 584#define I2C3_BASE_ADDR  0
 585#endif
 586
 587#if !defined(I2C4_BASE_ADDR)
 588#define I2C4_BASE_ADDR  0
 589#endif
 590
 591static struct mxc_i2c_bus mxc_i2c_buses[] = {
 592#if defined(CONFIG_ARCH_LS1021A) || defined(CONFIG_VF610) || \
 593        defined(CONFIG_FSL_LAYERSCAPE)
 594        { 0, I2C1_BASE_ADDR, I2C_QUIRK_FLAG },
 595        { 1, I2C2_BASE_ADDR, I2C_QUIRK_FLAG },
 596        { 2, I2C3_BASE_ADDR, I2C_QUIRK_FLAG },
 597        { 3, I2C4_BASE_ADDR, I2C_QUIRK_FLAG },
 598#else
 599        { 0, I2C1_BASE_ADDR, 0 },
 600        { 1, I2C2_BASE_ADDR, 0 },
 601        { 2, I2C3_BASE_ADDR, 0 },
 602        { 3, I2C4_BASE_ADDR, 0 },
 603#endif
 604};
 605
 606struct mxc_i2c_bus *i2c_get_base(struct i2c_adapter *adap)
 607{
 608        return &mxc_i2c_buses[adap->hwadapnr];
 609}
 610
 611static int mxc_i2c_read(struct i2c_adapter *adap, uint8_t chip,
 612                                uint addr, int alen, uint8_t *buffer,
 613                                int len)
 614{
 615        return bus_i2c_read(i2c_get_base(adap), chip, addr, alen, buffer, len);
 616}
 617
 618static int mxc_i2c_write(struct i2c_adapter *adap, uint8_t chip,
 619                                uint addr, int alen, uint8_t *buffer,
 620                                int len)
 621{
 622        return bus_i2c_write(i2c_get_base(adap), chip, addr, alen, buffer, len);
 623}
 624
 625/*
 626 * Test if a chip at a given address responds (probe the chip)
 627 */
 628static int mxc_i2c_probe(struct i2c_adapter *adap, uint8_t chip)
 629{
 630        return bus_i2c_write(i2c_get_base(adap), chip, 0, 0, NULL, 0);
 631}
 632
 633int __enable_i2c_clk(unsigned char enable, unsigned i2c_num)
 634{
 635        return 1;
 636}
 637int enable_i2c_clk(unsigned char enable, unsigned i2c_num)
 638        __attribute__((weak, alias("__enable_i2c_clk")));
 639
 640void bus_i2c_init(int index, int speed, int unused,
 641                  int (*idle_bus_fn)(void *p), void *idle_bus_data)
 642{
 643        int ret;
 644
 645        if (index >= ARRAY_SIZE(mxc_i2c_buses)) {
 646                debug("Error i2c index\n");
 647                return;
 648        }
 649
 650        /*
 651         * Warning: Be careful to allow the assignment to a static
 652         * variable here. This function could be called while U-Boot is
 653         * still running in flash memory. So such assignment is equal
 654         * to write data to flash without erasing.
 655         */
 656        if (idle_bus_fn)
 657                mxc_i2c_buses[index].idle_bus_fn = idle_bus_fn;
 658        if (idle_bus_data)
 659                mxc_i2c_buses[index].idle_bus_data = idle_bus_data;
 660
 661        ret = enable_i2c_clk(1, index);
 662        if (ret < 0) {
 663                debug("I2C-%d clk fail to enable.\n", index);
 664                return;
 665        }
 666
 667        bus_i2c_set_bus_speed(&mxc_i2c_buses[index], speed);
 668}
 669
 670/*
 671 * Early init I2C for prepare read the clk through I2C.
 672 */
 673void i2c_early_init_f(void)
 674{
 675        ulong base = mxc_i2c_buses[I2C_EARLY_INIT_INDEX].base;
 676        bool quirk = mxc_i2c_buses[I2C_EARLY_INIT_INDEX].driver_data
 677                                        & I2C_QUIRK_FLAG ? true : false;
 678        int reg_shift = quirk ? VF610_I2C_REGSHIFT : IMX_I2C_REGSHIFT;
 679
 680        /* Set I2C divider value */
 681        writeb(I2C_IFDR_DIV_CONSERVATIVE, base + (IFDR << reg_shift));
 682        /* Reset module */
 683        writeb(I2CR_IDIS, base + (I2CR << reg_shift));
 684        writeb(0, base + (I2SR << reg_shift));
 685        /* Enable I2C */
 686        writeb(I2CR_IEN, base + (I2CR << reg_shift));
 687}
 688
 689/*
 690 * Init I2C Bus
 691 */
 692static void mxc_i2c_init(struct i2c_adapter *adap, int speed, int slaveaddr)
 693{
 694        bus_i2c_init(adap->hwadapnr, speed, slaveaddr, NULL, NULL);
 695}
 696
 697/*
 698 * Set I2C Speed
 699 */
 700static u32 mxc_i2c_set_bus_speed(struct i2c_adapter *adap, uint speed)
 701{
 702        return bus_i2c_set_bus_speed(i2c_get_base(adap), speed);
 703}
 704
 705/*
 706 * Register mxc i2c adapters
 707 */
 708#ifdef CONFIG_SYS_I2C_MXC_I2C1
 709U_BOOT_I2C_ADAP_COMPLETE(mxc0, mxc_i2c_init, mxc_i2c_probe,
 710                         mxc_i2c_read, mxc_i2c_write,
 711                         mxc_i2c_set_bus_speed,
 712                         CONFIG_SYS_MXC_I2C1_SPEED,
 713                         CONFIG_SYS_MXC_I2C1_SLAVE, 0)
 714#endif
 715
 716#ifdef CONFIG_SYS_I2C_MXC_I2C2
 717U_BOOT_I2C_ADAP_COMPLETE(mxc1, mxc_i2c_init, mxc_i2c_probe,
 718                         mxc_i2c_read, mxc_i2c_write,
 719                         mxc_i2c_set_bus_speed,
 720                         CONFIG_SYS_MXC_I2C2_SPEED,
 721                         CONFIG_SYS_MXC_I2C2_SLAVE, 1)
 722#endif
 723
 724#ifdef CONFIG_SYS_I2C_MXC_I2C3
 725U_BOOT_I2C_ADAP_COMPLETE(mxc2, mxc_i2c_init, mxc_i2c_probe,
 726                         mxc_i2c_read, mxc_i2c_write,
 727                         mxc_i2c_set_bus_speed,
 728                         CONFIG_SYS_MXC_I2C3_SPEED,
 729                         CONFIG_SYS_MXC_I2C3_SLAVE, 2)
 730#endif
 731
 732#ifdef CONFIG_SYS_I2C_MXC_I2C4
 733U_BOOT_I2C_ADAP_COMPLETE(mxc3, mxc_i2c_init, mxc_i2c_probe,
 734                         mxc_i2c_read, mxc_i2c_write,
 735                         mxc_i2c_set_bus_speed,
 736                         CONFIG_SYS_MXC_I2C4_SPEED,
 737                         CONFIG_SYS_MXC_I2C4_SLAVE, 3)
 738#endif
 739
 740#else
 741
 742static int mxc_i2c_set_bus_speed(struct udevice *bus, unsigned int speed)
 743{
 744        struct mxc_i2c_bus *i2c_bus = dev_get_priv(bus);
 745
 746        return bus_i2c_set_bus_speed(i2c_bus, speed);
 747}
 748
 749static int mxc_i2c_probe(struct udevice *bus)
 750{
 751        struct mxc_i2c_bus *i2c_bus = dev_get_priv(bus);
 752        const void *fdt = gd->fdt_blob;
 753        int node = dev_of_offset(bus);
 754        fdt_addr_t addr;
 755        int ret, ret2;
 756
 757        i2c_bus->driver_data = dev_get_driver_data(bus);
 758
 759        addr = dev_get_addr(bus);
 760        if (addr == FDT_ADDR_T_NONE)
 761                return -ENODEV;
 762
 763        i2c_bus->base = addr;
 764        i2c_bus->index = bus->seq;
 765        i2c_bus->bus = bus;
 766
 767        /* Enable clk */
 768        ret = enable_i2c_clk(1, bus->seq);
 769        if (ret < 0)
 770                return ret;
 771
 772        /*
 773         * See Documentation/devicetree/bindings/i2c/i2c-imx.txt
 774         * Use gpio to force bus idle when necessary.
 775         */
 776        ret = fdt_stringlist_search(fdt, node, "pinctrl-names", "gpio");
 777        if (ret < 0) {
 778                debug("i2c bus %d at 0x%2lx, no gpio pinctrl state.\n", bus->seq, i2c_bus->base);
 779        } else {
 780                ret = gpio_request_by_name_nodev(fdt, node, "scl-gpios",
 781                                                 0, &i2c_bus->scl_gpio,
 782                                                 GPIOD_IS_OUT);
 783                ret2 = gpio_request_by_name_nodev(fdt, node, "sda-gpios",
 784                                                 0, &i2c_bus->sda_gpio,
 785                                                 GPIOD_IS_OUT);
 786                if (!dm_gpio_is_valid(&i2c_bus->sda_gpio) |
 787                    !dm_gpio_is_valid(&i2c_bus->scl_gpio) |
 788                    ret | ret2) {
 789                        dev_err(dev, "i2c bus %d at %lu, fail to request scl/sda gpio\n", bus->seq, i2c_bus->base);
 790                        return -ENODEV;
 791                }
 792        }
 793
 794        ret = i2c_idle_bus(i2c_bus);
 795        if (ret < 0) {
 796                /* Disable clk */
 797                enable_i2c_clk(0, bus->seq);
 798                return ret;
 799        }
 800
 801        /*
 802         * Pinmux settings are in board file now, until pinmux is supported,
 803         * we can set pinmux here in probe function.
 804         */
 805
 806        debug("i2c : controller bus %d at %lu , speed %d: ",
 807              bus->seq, i2c_bus->base,
 808              i2c_bus->speed);
 809
 810        return 0;
 811}
 812
 813static int mxc_i2c_probe_chip(struct udevice *bus, u32 chip_addr,
 814                              u32 chip_flags)
 815{
 816        int ret;
 817        struct mxc_i2c_bus *i2c_bus = dev_get_priv(bus);
 818
 819        ret = i2c_init_transfer(i2c_bus, chip_addr, 0, 0);
 820        if (ret < 0) {
 821                debug("%s failed, ret = %d\n", __func__, ret);
 822                return ret;
 823        }
 824
 825        i2c_imx_stop(i2c_bus);
 826
 827        return 0;
 828}
 829
 830static int mxc_i2c_xfer(struct udevice *bus, struct i2c_msg *msg, int nmsgs)
 831{
 832        struct mxc_i2c_bus *i2c_bus = dev_get_priv(bus);
 833        int ret = 0;
 834        ulong base = i2c_bus->base;
 835        int reg_shift = i2c_bus->driver_data & I2C_QUIRK_FLAG ?
 836                VF610_I2C_REGSHIFT : IMX_I2C_REGSHIFT;
 837
 838        /*
 839         * Here the 3rd parameter addr and the 4th one alen are set to 0,
 840         * because here we only want to send out chip address. The register
 841         * address is wrapped in msg.
 842         */
 843        ret = i2c_init_transfer(i2c_bus, msg->addr, 0, 0);
 844        if (ret < 0) {
 845                debug("i2c_init_transfer error: %d\n", ret);
 846                return ret;
 847        }
 848
 849        for (; nmsgs > 0; nmsgs--, msg++) {
 850                bool next_is_read = nmsgs > 1 && (msg[1].flags & I2C_M_RD);
 851                debug("i2c_xfer: chip=0x%x, len=0x%x\n", msg->addr, msg->len);
 852                if (msg->flags & I2C_M_RD)
 853                        ret = i2c_read_data(i2c_bus, msg->addr, msg->buf,
 854                                            msg->len);
 855                else {
 856                        ret = i2c_write_data(i2c_bus, msg->addr, msg->buf,
 857                                             msg->len);
 858                        if (ret)
 859                                break;
 860                        if (next_is_read) {
 861                                /* Reuse ret */
 862                                ret = readb(base + (I2CR << reg_shift));
 863                                ret |= I2CR_RSTA;
 864                                writeb(ret, base + (I2CR << reg_shift));
 865
 866                                ret = tx_byte(i2c_bus, (msg->addr << 1) | 1);
 867                                if (ret < 0) {
 868                                        i2c_imx_stop(i2c_bus);
 869                                        break;
 870                                }
 871                        }
 872                }
 873        }
 874
 875        if (ret)
 876                debug("i2c_write: error sending\n");
 877
 878        i2c_imx_stop(i2c_bus);
 879
 880        return ret;
 881}
 882
 883static const struct dm_i2c_ops mxc_i2c_ops = {
 884        .xfer           = mxc_i2c_xfer,
 885        .probe_chip     = mxc_i2c_probe_chip,
 886        .set_bus_speed  = mxc_i2c_set_bus_speed,
 887};
 888
 889static const struct udevice_id mxc_i2c_ids[] = {
 890        { .compatible = "fsl,imx21-i2c", },
 891        { .compatible = "fsl,vf610-i2c", .data = I2C_QUIRK_FLAG, },
 892        {}
 893};
 894
 895U_BOOT_DRIVER(i2c_mxc) = {
 896        .name = "i2c_mxc",
 897        .id = UCLASS_I2C,
 898        .of_match = mxc_i2c_ids,
 899        .probe = mxc_i2c_probe,
 900        .priv_auto_alloc_size = sizeof(struct mxc_i2c_bus),
 901        .ops = &mxc_i2c_ops,
 902};
 903#endif
 904